`<template>
  <div class="my-tab-bar">
  	<div 
    class="tab-item" 
    v-for='(item, index) in list' 
    :key='index'
    :class="{ current: index === activeIndex}"
    @click="clickFn(index,item.componentName)">
      <!-- 图标 -->
      <span class="iconfont" :class="item.iconText"></span>
      <!-- 文字 -->
      <span>{{ item.text }}</span>
    </div>
  </div>
</template>

<script>
export default {
  // 接收父的数据
  props:{
    list: {
      type: Array,//数据类型为数组
      required: true,//数据依赖
      validator(val){
        //validator验证器
        // val 就是传过来的数据list，此函数中我们可以返回true或者false
        if(val.length < 2 || val.length > 5){
          console.error('prop list must between 2 and 5');
          return false
        }
        return true
      }
    }
  },
  data(){
    return {
      activeIndex: 0//默认第一个高亮
    }
  },
  methods: {
    clickFn(index,componentName){
      this.activeIndex = index //点谁就保存谁的index值
      this.$emit('changeCom', componentName)
    }
  }
}
</script>

<style lang="less" scoped>
.my-tab-bar {
  position: fixed;
  left: 0;
  bottom: 0;
  width: 100%;
  height: 50px;
  border-top: 1px solid #ccc;
  display: flex;
  justify-content: space-around;
  align-items: center;
  background-color: white;
  .tab-item {
    display: flex;
    flex-direction: column;
    align-items: center;
  }
}
    
.current {
  color: #1d7bff;
}
</style>